Considerable information is now available that dolichol oligosaccharide intermediates are involved in the synthesis of asparagine-linked carbohydrate chains. Furthermore, evidence is accumulating that following transfer of the oligosaccharide Glc3Man9GlcNAc2 from the lipid carrier to protein, a processing mechanism exists that leads to formation of either high mannose or complex units. The objective of this investigation is the elucidation of those factors or enzymatic reactions that requlate the assembly of these oligosaccharide units in cultured mammalian cells. The regulation of glycosylation of protein will be approached by examining the effect of glucose deprivation on the glycosylation of the G-protein in vesicular stomatitis virus-infected BHK cells. From the results of our preliminary experiments, as well as from the work of others, there is reason to believe that protein glycosylation is controlled by celluar levels of glucose (or a glucose derivative). These levels would have a direct influence on the enzymatic attachment of glucose residues to complete the synthesis of Glc3Man9GlcNAc2-P-P-Dol, resulting in efficient glycosylation of protein. Alternatively it is possible that glucose or a metabolite of glucose serves as a modulator in regulating a particular enzyme of the pathway. The lipid-linked and protein-bound intermediates synthesized in VSV-infected glucose starved BHK cells will be analyzed qualitatively by in vivo studies and quantitated with the aid of sodium (3H)borohydride. In vitro experiments will be conducted to determine whether the activity of one or more of the enzymes involved in glycosylation is decreased following glucose deprivation and whether glucose or a metabolite of glucose is an effector of protein glycosylation.